SUMMARY Increased levels of androgens, such as testosterone (T), in women are associated with infertility, as well as an increased risk of metabolic dysfunction in endocrine disorders such as polycystic ovary syndrome (PCOS) and congenital adrenal hyperplasia. PCOS in particular is the most common reproductive disorder, affecting up to 12% of women in the US. PCOS is also associated with an increased risk for gestational diabetes and subsequent type-2 diabetes. While elevated androgen levels alone contribute to metabolic disease, many women with PCOS are also obese, which independently increases the risk for gestational and type-2 diabetes. The relationship between androgens and obesity in PCOS is further complicated by studies demonstrating that obesity also affects fertility, so that obese women with PCOS may have an increased degree of infertility. Obesity is driven in most cases by reduced physical activity and, to an even greater degree, by consumption of high-fat Western-style diet (WSD). To investigate the interaction between androgen and obesity in inducing metabolic disease and infertility in women, we developed in the current NCTRI a nonhuman primate model of chronic hyperandrogenemia (elevated T) in the presence or absence of a WSD, beginning at puberty. Over the first 3 years of treatment, we found that the combination of T and WSD worsened systemic measures of metabolism (obesity and insulin resistance) and produced specific changes in adipose tissue such as enlarged visceral adipocytes, increased insulin-stimulated fatty acid uptake, and decreased lipolysis. Notably, animals that were exposed to the WSD with or without T exhibited elevated insulin levels with normal glucose levels, suggesting that, at this stage, the increased insulin was still sufficient to overcome insulin resistance. However, this subclinical insulin resistance was associated with decreased fertility and viable pregnancies by year 4 of treatment, indicating that even mild subclinical insulin resistance can reduce fertility. These data lead to our hypothesis that: a) worsening metabolic status due to continued chronic T and/or WSD will exert adverse effects on maternal gestational metabolic health; b) that some aspects of poor metabolic status will remain after removal of T and WSD due to epigenetic changes; and c) that these persistent effects will compromise maternal metabolic health during subsequent pregnancy. To address this hypothesis, we propose the following specific aims in this NCTRI renewal application: 1. Compare the effects of hyperandrogenemia and/or WSD on metabolic health during and after pregnancy. 2. Characterize how removal of hyperandrogenemia and/or WSD alters metabolic health and epigenetic programming of gene expression in adipose tissue. 3. Examine how reversal of hyperandrogenemia and/or WSD alters metabolic health during pregnancy.